The human species came into being at the time of the greatest biologic

Question

The human species came into being at the time of the greatest biological diversity in the history of the Earth. Today, as human populations expand and alter the natural environment, they are reducing biological diversity to its lowest level since the end of the Mesozoic era, 65 million years ago. The ultimate consequences of this biological collision are beyond calculation, but they are certain to be harmful. That, in essence, is the biodiversity crisis.

The history of global diversity can be summarized as follows: after the initial flowering of multicellular animals, there was a swift rise in the number of species in early Paleozoic times (between 600 and 430 million years ago), then plateaulike stagnation for the remaining 200 million years of the Paleozoic era, and finally a slow but steady climb through the Mesozoic and Cenozoic eras to diversity’s all-time high. This history suggests that biological diversity was hard won and a long time in coming.  Furthermore, this pattern of increase was set back by five massive extinction episodes. The most recent of these, during the Cretaceous period, is by far the most famous, because it ended the age of the dinosaurs, conferred hegemony on the mammals, and ultimately made possible the ascendancy of the human species. But the cretaceous crisis was minor compared with the Permian extinctions 240 million years ago, during which between 77 and 96 percent of marine animal species perished. It took 5 million years, well into Mesozoic times, for species diversity to begin a significant recovery.

Within the past 10,000 years biological diversity has entered a wholly new era. Human activity has had a devastating effect on species diversity, and the rate of human-induced extinctions is accelerating. Half of the bird species of Polynesia have been eliminated through hunting and the destruction of native forests. Hundreds of fish species endemic to Lake Victoria are now threatened with extinction following the careless introduction of one species of fish, the Nile perch. The list of such biogeographic disasters is extensive.

Because every species is unique and irreplaceable, the loss of biodiversity is the most profound process of environmental change. Its consequences are also the least predictable because the value of Earth’s biota (the fauna and flora collectively) remains largely unstudied and unappreciated; unlike material and cultural wealth, which we understand because they are the substance of our everyday lives, biological wealth is usually taken for granted. This is a serious strategic error, one that will be increasingly regretted as time passes. The biota is not only part of a country’s heritage, the product of millions of years of evolution centered on that place; it is also a potential source for immense untapped material wealth in the form of food, medicine, and other commercially important substance.   1 
 1. Which one of the following best expresses the main idea of the passage?

(A) The reduction in biodiversity is an irreversible process that represents a setback both for science and for society as a whole.
(B) The material and cultural wealth of a nation are insignificant when compared with the country’s biological wealth.
(C) The enormous diversity of life on Earth could not have come about without periodic extinctions that have conferred preeminence on one species at the expense of another.
(D) The human species is in the process of initiating a massive extinction episode that may make past episodes look minor by comparison.
(E) The current decline in species diversity is human-induced tragedy of incalculable proportions that has potentially grave consequences for the human species.

2 
 2. Which one of the following situations is most analogous to the history of global diversity summarized in Highlighted part of the passage?

(A) The number of fish in a lake declines abruptly as a result of water pollution, then makes a slow comeback after cleanup efforts and the passage of ordinances against dumping.
(B) The concentration of chlorine in the water supply of large city fluctuates widely before stabilizing at a constant and safe level.
(C) An old-fashioned article of clothing goes in and out of style periodically as a result of features in fashion magazines and the popularity of certain period films.
(D) After valuable mineral deposits are discovered, the population of a geographic region booms then levels off and begins to decrease at a slow and steady pace.
(E) The variety of styles stocked by a shoe store increases rapidly after the store opens, holds constant for many months, and then gradually creeps upward.

3 
 3. The author suggests which one of the following about the Cretaceous crisis?

(A) It was the second most devastating extinction episode in history.
(B) It was the most devastating extinction episode up until that time.
(C) It was less devastating to species diversity than is the current biodiversity crisis.
(D) The rate of extinction among marine animal species as a result of the crisis did not approach 77 percent.
(E) The dinosaurs comprised the great majority of species that perished during the crisis.

4 
 4. The author mentions the Nile perch in order to provide an example of

(A) a species that has become extinct through human activity
(B) the typical lack of foresight that has led to biogeographic disaster
(C) a marine animal species that survived the Permian extinctions
(D) a species that is a potential source of material wealth
(E) the kind of action that is necessary to reverse the decline in species diversity

5 
 5. All of the following are explicitly mentioned in the passage as contributing to the extinction of species  EXCEPT

(A) hunting
(B) pollution
(C) deforestation
(D) the growth of human populations
(E) human-engineered changes in the environment

6 
 6. The passage suggests which one of the following about material and cultural wealth?

(A) Because we can readily assess the value of material and cultural wealth, we tend not to take them for granted.
(B) Just as the biota is a source of potential material wealth, it is an untapped source of cultural wealth as well.
(C) Some degree of material and cultural wealth may have to be sacrificed if we are to protect our biological heritage.
(D) Material and cultural wealth are of less value than biological wealth because they have evolved over a shorter period of time.
(E) Material wealth and biological wealth are interdependent in a way that material wealth and cultural wealth are not.

7 
 7. The author would be most likely to agree with which one of the following statements about the consequences of the biodiversity crisis?

(A) The loss of species diversity will have as immediate an impact on the material of nations as on their biological wealth.
(B) The crisis will likely end the hegemony of the human race and bring about the ascendancy of another species.
(C) The effects of the loss of species diversity will be dire, but we cannot yet tell how dire.
(D) It is more fruitful to discuss the consequences of the crisis in terms of the potential loss to humanity than in strictly biological loss to humanity than in strictly biological terms.
(E) The consequences of the crisis can be minimized, but the pace of extinctions can not be reversed.

dcummins · Accepted Answer

Map:
 P1: Author sets context and defines a problem - biodiversity is in real decline as a result of humans
P2: Author provides background context on biodiversity trends and causes - extinctions and time periods. Para 2 foreshadows P3
P3: Author states the severity of human impact and gives examples
P4: Author concludes the severity of this continued trend and explores potential factors why the trend is the way it is
purpose: descriptive -ve / arguing against current conditions

Got 2 questions incorrect overall as below.

1. Which one of the following best expresses the main idea of the passage?
 A - Initially I actually chose A, but looking at it again out of test I realise A is incorrect because the passage deals more with the human impact on biodiversity than the consequences of reduction of biodiversity itself on science or society.
B- is incorrect as the author doesn't discuss the wealth of a nation. He states that people don't appreciate biodiversity because its immaterial and thus hard to add monetary value to.
C - This is incorrect. We know Biodiversity was at its peak at the beginning of time.
D - no. Way too specific and not even supported.
E- I initially marked this wrong because of the heavy wording - "tradgedy of incalculable proportions" - but in actuality this is the only answer choice that captures the intention of the author: to define the severity of human impacts to biodiversity.

2. Which one of the following situations is most analogous to the history of global diversity summarized in Highlighted part of the passage?
 Note:The highlighted text shows a situation where something increases dramatically, stabilises, the slowly climbs up over time. We need something that emulates this trend.

A - shows a decline trend - can stop here. Elim
B - fluctuation is not equal to the trend we want. Eliminate 
C - In and Out is similar to fluctuating - eliminate
D - No. Shows that something ends up declining - elim.
 E - increase rapidly, holds steady, gradually increases again --perfect

3. The author suggests which one of the following about the Cretaceous crisis?
 A - Again, I incorrectly marked this correct as I read "it was the second most" and then I recall that the Cretaceous extinctions were "minor compared to" another extinction. In actuality the author merely makes a comparison, he doesn't openly state or imply that Cretaceous was the second largest. In fact we only know that the "permian extinctions" were the largest.
B - No. We know it was "minor compared to the Permian"
C - Can't be supported.
 D  - I missed this in the beginning, but its correct because if it were approaching the "77 and 96" extinction rate among marine species then it wouldn't be "MINOR" compared to the period in which the extinction of marine species hit this threshold.
E - Can't be supported. We just know that Dinosaurs were part of the Cretacious period. Among Dinosaurs were other "mammals" and humans.

4. The author mentions the Nile perch in order to provide an example of
 A - no. It's a pest.
 B  - Yes. The perch was introduced by humans. If they had foresight to detect the perchs' impact then they wouldn't have introduced it.
C - No. Cannot be supported at all.
D - what? No.
E - No. Its given as an example of a decline not the opposite.

5. All of the following are explicitly mentioned in the passage as contributing to the extinction of species EXCEPT  -  This question actually took me a while to answer!
 
A and C - stated in Para 3 "hunting and destruction of native rain forests"
D and E - stated in Para 1 - "as human populations expand and alter the natural environment"

Looked for a synonym of  B , but didn't find it. B is the answer

6. The passage suggests which one of the following about material and cultural wealth?
 Pre-think this before looking at the answers: The author mentions material wealth in the closing passage to state that people don't "understand" the loss of biodiversity because its not substance in every day lives and thus "taken for granted"

A  - This is correct. 
B - No. Absolutely not.
C - No. We cant support this.
D - This is completely false. Nothing is mentioned of material and cultural wealth prior to the last para.
E - No. The relationship between material and cultural wealth isn't touched.

7. The author would be most likely to agree with which one of the following statements about the consequences of the biodiversity crisis?
 A - no. We cannot support this. There is no information on the interplay between material and bio wealth
B - No. This is a step wayyyy to far. Hegemony = reign of control. Humans have been around since inception of biodiversity as per first para, so why would we conclude that they suddenly go?
 C  - Yes. That is the issue with changes to biodiversity. We can't measure or predict the impacts. As exemplified by the nile perch.
D - No. They're fairly related.
E - We can't support this at all. Extinct = gone forever.

patto · Answer

For question #3, the correct answer is D.

Let's take a closer look to the part of the passage where the Cretaceous period is quoted.
"But the cretaceous crisis was minor compared with the Permian extinctions 240 million years ago, during which between 77 and 96 percent of marine animal species perished."

Here we can noticed that the CRETACEOUS CRISIS was not as bad as the Permian Crisis, which indeed had a 0.77<ratio of extinction<0.96.

Therefore, we can conclude that the ratio of extinction of the CRETACEOUS CRISIS did not approach the 77 percent. Then, the correct answer choice, clearly suggested by the passage, is D: " The rate of extinction among marine animal species as a result of the crisis did not approach 77 percent."

I think question #3 is good!!

Sajjad1994 · Answer

Explanation

6. The passage suggests which one of the following about material and cultural wealth?

Explanation

Back to  Para 4  for this one: In lines 38-42, the author argues that humans take biological wealth for granted because they don’t understand its value. In contrast, he suggests, because humans understand the value of material and cultural wealth, these things aren’t taken for granted.

(B), (E)  The distinction in  Para 4  is between material / cultural wealth, on the one hand, and biological wealth, on the other. The connections offered in these two choices distort and expand upon this distinction, and are in no way suggested by the author.

(C)  The author implies just the opposite—that preserving our biological wealth will enhance our material wealth and preserve our cultural heritage.

(D)  serves up an unsupported comparison that isn’t implied in the passage. The author doesn’t rank the importance of material and cultural wealth as opposed to biological wealth (he seems to think that all are important to humanity)—he merely contrasts our understanding and appreciation of each.

• When a question focuses on one very specific idea (as this one does), re-read the idea to make sure that you’re absolutely clear about it. This way you won’t fall for choices that use the passage’s language but distort its content.

Answer: A

GMATNinja · Answer

Excellent work as always,  SajjadAhmad !

Yep, this one relates to the following portion: "the value of Earth’s biota (the fauna and flora collectively) remains largely unstudied and unappreciated; unlike material and cultural wealth,  which we understand because they are the substance of our everyday lives ,  biological wealth is usually taken for granted ."

UNLIKE material and cultural wealth, biological wealth is usually taken for granted. From this, we can infer than material and cultural wealth are generally NOT taken for granted.

We don't take material and cultural wealth for granted because they are the substance of our everyday lives. We appreciate their value because we  experience  that value in our everyday lives. In other words, because we experience them in our everyday lives, we can readily assess their value, as stated in choice (A).

Bhavyam · Answer

Yes, I had marked answer for 3rd question as E using the logic I posted in the previous comment. Why is that logic incorrect?

Sajjad1994 · Answer

Alright !

In lines 21-23, the author mentions that between 77 and 96 percent of all marine animal species became extinct during the Permian extinction episode. In lines 20-21, the author says that the Cretaceous extinction episode was  “minor”  in comparison to the Permian. Thus, we can  conclude that  less than 77 percent of marine animal species became extinct during the  “Cretaceous crisis.”

(E) is wrong  because this extinction period was marked by the disappearance of the dinosaurs; this is only what makes it the  “most famous”  extinction episode. However, this doesn’t necessarily mean that the dinosaurs  “comprised the great majority of species that perished during the crisis.”  For all we know, many more non-dinosaur species may have perished during this crisis.

• Correct answers will generally be worded somewhat differently than the passage itself.

hope it helps

auradediligodo · Answer

Hi everyone,
Took 17 minutes and got 6/7 correct. Took 5 minutes to read, write down paragraph summaries and main point.

P1: biodiversity crisis
P2:History of global diversity and extinctions
P3:Human activity effect on biodiversity
P4:Loss biodiversity effect on biota

MP: present biodiversity crisis and the role of human activity in it

1.  Which one of the following best expresses the main idea of the passage?

Pre-thinking:
 refer to our main point formulation for this question

(A) The reduction in biodiversity is an irreversible process that represents a setback both for science and for society as a whole.
 Nowhere it is said that the reduction is irreversible. Hence incorrect

(B) The material and cultural wealth of a nation are insignificant when compared with the country’s biological wealth.
 This is related only to the last paragraph of the passage. Hence partial scope and incorrect

(C) The enormous diversity of life on Earth could not have come about without periodic extinctions that have conferred preeminence on one species at the expense of another.
 This is related only to the second paragraph. Plus diversity size is not  only  caused by periodic extinctions. Hence incorrect

(D) The human species is in the process of initiating a massive extinction episode that may make past episodes look minor by comparison.
 Never mentioned. Hence incorrect

(E) The current decline in species diversity is human-induced tragedy of incalculable proportions that has potentially grave consequences for the human species.
 This is in line with what the passage as a whole communicates. Hence correct

2.  Which one of the following situations is most analogous to the history of global diversity summarized in Highlighted part of the passage?

Pre-thinking:
 refer to the highlighted portion. It talks about an initial rise->fast rise->stop (stagnation)->slow constant rise.
Any option suggesting a similar trend will be our answer

(A) The number of fish in a lake declines abruptly as a result of water pollution, then makes a slow comeback after cleanup efforts and the passage of ordinances against dumping.
 no decline discussed. Hence incorrect

(B) The concentration of chlorine in the water supply of large city fluctuates widely before stabilizing at a constant and safe level.
 no fluctuation. Hence incorrect

(C) An old-fashioned article of clothing goes in and out of style periodically as a result of features in fashion magazines and the popularity of certain period films.
 again no fluctuation. Hence incorrect

(D) After valuable mineral deposits are discovered, the population of a geographic region booms then levels off and begins to decrease at a slow and steady pace.
 inconsistent for the last phase. There is a constant rise not a constant decrease. Hence incorrect

(E) The variety of styles stocked by a shoe store increases rapidly after the store opens, holds constant for many months, and then gradually creeps upward.
 In line with our Prethinking. Hence correct

3.  The author suggests which one of the following about the Cretaceous crisis?

Pre-thinking:
 Refer to P2 and especially to the non-underlined portion of the paragraph.
attributes: 
-most recent
-most famous
-ended dinosaurs age
-minor compared to PE

(A) It was the second most devastating extinction episode in history.
 Cannot be inferred. It was one of the most recent and famous but no information whether it was the 2nd most important. Hence incorrect

(B) It was the most devastating extinction episode up until that time.
 no. it was a minor one compared to one of the previous (PE). Hence incorrect

(C) It was less devastating to species diversity than is the current biodiversity crisis.
 Cannot be inferred by the given information. Hence incorrect

(D) The rate of extinction among marine animal species as a result of the crisis did not approach 77 percent.
 We are given that Ccrisis was minor compared to PE where that rate was approached. This is a reasonable inference to make given the information although the scenario in which Ccrisis approached that rate but was still minor compared to PE is a possibility. Hence correct

(E) The dinosaurs comprised the great majority of species that perished during the crisis.
 The information given says that Ccrisis is  famous  for ending the dinosaurs age but it does not say that other species could have been eliminated more significantly. Hence incorrect.

4.  The author mentions the Nile perch in order to provide an example of

Pre-thinking:
 Refer to P3 and especially to: "Hundreds of fish species endemic to Lake Victoria are now threatened with extinction  following the careless introduction  of one species of fish, the Nile perch."

(A) a species that has become extinct through human activity
 The nile perch was the reason for other species to become extinct. Hence incrrect

(B) the typical lack of foresight that has led to biogeographic disaster
 As the underlined portion in our pre-thinking says the introduction of nile perch was careless. So it makes sense to say that there was a lack of foresight. Hence correct

(C) a marine animal species that survived the Permian extinctions
 out of context and incorrect.

(D) a species that is a potential source of material wealth
 Out of context here. Hence incorrect

(E) the kind of action that is necessary to reverse the decline in species diversity
 I'd say opposite. Carefulness on the contrary would have helped to preserve diversity in this case. Hence incorrect

5.  All of the following are explicitly mentioned in the passage as contributing to the extinction of species EXCEPT

Pre-thinking:
 Many factors contributing to extinction are mentioned in P1 and P3 so I would work on them for answering this question.

(A) hunting
 Mentioned in P3. Hence incorrect

(B) pollution
 Although our common knowledge would mark this answer as correct this factor is never mentioned in the passage. Hence correct

(C) deforestation
 Mentioned in P3. Hence incorrect

(D) the growth of human populations
 Mentioned in P1. Hence incorrect

(E) human-engineered changes in the environment
 Mentioned in P1. Hence incorrect

6 . The passage suggests which one of the following about material and cultural wealth?

Pre-thinking: 
 M&CW are discussed in the last paragraph. Refer to these line especially : "unlike material and cultural wealth, which we understand because they are the substance of our everyday lives, biological wealth is usually taken for granted."
So:
- we understand M&CW because we see them every day 
- the previous bullet point is in contrast with biological wealth, which is taken for granted
So an inference that we can make is that we would understand better biological wealth if we saw it every day and that we don't take M&CW for granted since we see them everyday

(A) Because we can readily assess the value of material and cultural wealth, we tend not to take them for granted.
 In line with prethinking. Hence correct

(B) Just as the biota is a source of potential material wealth, it is an untapped source of cultural wealth as well.
 Cannot be inferred by the information in the passage. Hence incorrect

(C) Some degree of material and cultural wealth may have to be sacrificed if we are to protect our biological heritage.
 Cannot be inferred by the given information. Hence incorrect

(D) Material and cultural wealth are of less value than biological wealth because they have evolved over a shorter period of time.
 Cannot be inferred by the given information. Hence incorrect

(E) Material wealth and biological wealth are interdependent in a way that material wealth and cultural wealth are not.
Cannot be inferred by the information given. Hence incorrect

7.  The author would be most likely to agree with which one of the following statements about the consequences of the biodiversity crisis?

Pre-thinking:
 Consequences are discussed in P1: "The ultimate consequences of this biological collision are beyond calculation, but they are certain to be harmful. That, in essence, is the biodiversity crisis."

(A) The loss of species diversity will have as immediate an impact on the material of nations as on their biological wealth.
 Inconsistent because of immediate. Hence incorrect

(B) The crisis will likely end the hegemony of the human race and bring about the ascendancy of another species.
 Never mentioned and quite funny statement. Hence incorrect

(C) The effects of the loss of species diversity will be dire, but we cannot yet tell how dire.
 in line with the portion highlighted in the pre-thinking. Hence correct

(D) It is more fruitful to discuss the consequences of the crisis in terms of the potential loss to humanity than in strictly biological loss to humanity than in strictly biological terms.
 Never mentioned. Hence incorrect

(E) The consequences of the crisis can be minimized, but the pace of extinctions can not be reversed.
 Never mentioned. Hence incorrect

AnushkaPatel961 · Answer

P1: Intro
Author; Bio crisis harmful

P2: Bio div took long time; Diff crisis

P3: Human act decrease bio div; Example

P4: bio decrease=Envi change
Author: Bio Imp

1. Which one of the following best expresses the main idea of the passage?

(A) The reduction in biodiversity is an  irreversible  process that represents a  setback both for science and for society  as a whole.-not given
(B) The material and cultural wealth of a nation are insignificant when compared with the country’s biological wealth.-only last para
(C) The  enormous diversity of life on Earth could not have come about  without periodic extinctions that have conferred preeminence on one species at the  expense of another. -exaggerated inference of a para
(D) The human species is in the  process of initiating a massive extinction episode  that may make past episodes look minor by comparison.-talked about harmful not extinction.
(E) The current decline in species diversity is human-induced tragedy of incalculable proportions that has potentially grave consequences for the human species.-correct

2. Which one of the following situations is most analogous to the history of global diversity summarized in Highlighted part of the passage?

(A) The number of fish in a lake declines abruptly as a result of water pollution, then makes a slow comeback after cleanup efforts and the passage of ordinances against dumping.
(B) The concentration of chlorine in the water supply of large city fluctuates widely before stabilizing at a constant and safe level.
(C) An old-fashioned article of clothing goes in and out of style periodically as a result of features in fashion magazines and the popularity of certain period films.
(D) After valuable mineral deposits are discovered, the population of a geographic region booms then levels off and begins to decrease at a slow and steady pace.
(E) The variety of styles stocked by a shoe store  increases  rapidly after the store opens, holds  constant  for many months, and then  gradually creeps upward .-correct

History summary: Sharp inc; stagnation; slow inc.

3. The author suggests which one of the following about the Cretaceous crisis?

(A) It was the  secon d most devastating extinction episode in history.- no rank given
(B) It was the  most devastating  extinction episode up until that time.- not given
(C) It was  less devastating to species diversity   than is the current biodiversity crisi s.-irrelevant comparison
(D) The rate of extinction among marine animal species as a result of the crisis did not approach 77 percent.-correct
(E) The  dinosaurs comprised the great majority of species  that perished during the crisis.-cannot be infered

4. The author mentions the Nile perch in order to provide an example of

(A) a species that has become  extinct  through human activity
(B) the typical lack of foresight that has led to biogeographic disaster-the line in italics
(C) a marine animal species that  survived the Permian extinctions 
(D) a species that is a  potential source of material wealth 
(E) the kind of  action that is necessary to reverse  the decline in species diversity

Here the knowledge of SC can help you identify what Nile Perch is
Hundreds of  fish species  endemic to Lake Victoria are now  threatened  with extinction following the  careless introduction of one species of fish , the Nile perch.  The list of such biogeographic disasters is extensive. 
The underlined part is referring to Nile Perch. From the Bold and underlined part it can be infered that the Nile Perch has entered in the threat of extinction list.

All of the following are explicitly mentioned in the passage as contributing to the extinction of species EXCEPT

(A) hunting
(B) pollution
(C) deforestation
(D) the growth of human populations
(E) human-engineered changes in the environment

I was confused between B and D. Chose B as it was nowhere mentioned in the passage.

6. The passage suggests which one of the following about material and cultural wealth?

(A) Because we can readily assess the value of material and cultural wealth, we tend not to take them for granted.- inferred from  unlike material and cultural wealth, which we understand because they are the substance of our everyday lives, biological wealth is usually taken for granted. 
(B) Just as the biota is a source of potential material wealth, it is an untapped source of cultural wealth as well.
(C) Some degree of material and cultural wealth may have to be sacrificed if we are to protect our biological heritage.
(D) Material and cultural wealth are of less value than biological wealth because they have evolved over a shorter period of time.
(E) Material wealth and biological wealth are interdependent in a way that material wealth and cultural wealth are not.

7. The author would be most likely to agree with which one of the following statements about the consequences of the biodiversity crisis?

(A) The loss of species diversity will have as immediate an impact on the material of nations as on their biological wealth.
(B) The crisis will likely end the hegemony of the human race and bring about the ascendancy of another species.
(C) The effects of the loss of species diversity will be dire, but we cannot yet tell how dire. - P1  The ultimate consequences of this biological collision are beyond calculation, but they are certain to be harmful. That, in essence, is the biodiversity crisis. 
(D) It is more fruitful to discuss the consequences of the crisis in terms of the potential loss to humanity than in strictly biological loss to humanity than in strictly biological terms.
(E) The consequences of the crisis can be minimized, but the pace of extinctions can not be reversed.

Hit Kudos if you found it helpful

ishita27 · Answer

Hi, In question 1. Why can't D be correct? Or am I understanding it differently? Please explain  GMATNinja   SajjadAhmad

Reference for D is found in the first para:
"Today, as human populations expand and alter the natural environment, they are reducing biological diversity to its lowest level since the end of the Mesozoic era, 65 million years ago. "

Sajjad1994 · Answer

Why D is wrong

(D)  is too extreme. While the author suggests that today’s biodiversity crisis is a potential disaster,  he doesn’t imply that it could be worse than past episodes of mass extinction.

Thank you

VerbalBot · Answer

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